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exhauster. Every given mathmatical theory must,
in that sense, eventually become exhausted. Whether
or not new theories ^{of interest} will continue to offer new
problems or not, I am not prepared to say.

But to come back to the matter in hand, I
give you without further preface, the following
rule for positively, ascertaining whether or not
a given graph is beta possible.

In the first place find in the graph every
lexis, (regarding θ as a lexis), of which
one replica is oddly enclosed ^{that it is within an odd number of cuts)} and another
evenly enclosed ^{[???} within an even number of cuts} the latter not being enclosed
by every cut that encloses the former; and
call every such pair of spots an adaptible
pair. Having found such an adaptible pair An adaptible pair is said to be conjoined